[PATCH 07/15] MIPS: Setup boot_command_line before plat_mem_setup

From: Paul Cercueil
Date: Wed Jun 07 2017 - 16:07:55 EST


From: Paul Burton <paul.burton@xxxxxxxxxx>

Platforms using DT will typically call __dt_setup_arch from
plat_mem_setup. This in turn calls early_init_dt_scan. When
CONFIG_CMDLINE is set, this leads to its value being copied into
boot_command_line by early_init_dt_scan_chosen. If this happens before
the code setting up boot_command_line in arch_mem_init runs, that code
will go on to append CONFIG_CMDLINE (via builtin_cmdline) to
boot_command_line again, duplicating it. For some command line
parameters (eg. earlycon) this can be a problem. Set up
boot_command_line before early_init_dt_scan_chosen gets called such that
it will not write CONFIG_CMDLINE in this scenario & the arguments aren't
duplicated.

Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
---
arch/mips/kernel/setup.c | 39 ++++++++++++++++++++-------------------
1 file changed, 20 insertions(+), 19 deletions(-)

diff --git a/arch/mips/kernel/setup.c b/arch/mips/kernel/setup.c
index 01d1dbde5fbf..89785600fde4 100644
--- a/arch/mips/kernel/setup.c
+++ b/arch/mips/kernel/setup.c
@@ -785,25 +785,6 @@ static void __init arch_mem_init(char **cmdline_p)
struct memblock_region *reg;
extern void plat_mem_setup(void);

- /* call board setup routine */
- plat_mem_setup();
-
- /*
- * Make sure all kernel memory is in the maps. The "UP" and
- * "DOWN" are opposite for initdata since if it crosses over
- * into another memory section you don't want that to be
- * freed when the initdata is freed.
- */
- arch_mem_addpart(PFN_DOWN(__pa_symbol(&_text)) << PAGE_SHIFT,
- PFN_UP(__pa_symbol(&_edata)) << PAGE_SHIFT,
- BOOT_MEM_RAM);
- arch_mem_addpart(PFN_UP(__pa_symbol(&__init_begin)) << PAGE_SHIFT,
- PFN_DOWN(__pa_symbol(&__init_end)) << PAGE_SHIFT,
- BOOT_MEM_INIT_RAM);
-
- pr_info("Determined physical RAM map:\n");
- print_memory_map();
-
#if defined(CONFIG_CMDLINE_BOOL) && defined(CONFIG_CMDLINE_OVERRIDE)
strlcpy(boot_command_line, builtin_cmdline, COMMAND_LINE_SIZE);
#else
@@ -831,6 +812,26 @@ static void __init arch_mem_init(char **cmdline_p)
}
#endif
#endif
+
+ /* call board setup routine */
+ plat_mem_setup();
+
+ /*
+ * Make sure all kernel memory is in the maps. The "UP" and
+ * "DOWN" are opposite for initdata since if it crosses over
+ * into another memory section you don't want that to be
+ * freed when the initdata is freed.
+ */
+ arch_mem_addpart(PFN_DOWN(__pa_symbol(&_text)) << PAGE_SHIFT,
+ PFN_UP(__pa_symbol(&_edata)) << PAGE_SHIFT,
+ BOOT_MEM_RAM);
+ arch_mem_addpart(PFN_UP(__pa_symbol(&__init_begin)) << PAGE_SHIFT,
+ PFN_DOWN(__pa_symbol(&__init_end)) << PAGE_SHIFT,
+ BOOT_MEM_INIT_RAM);
+
+ pr_info("Determined physical RAM map:\n");
+ print_memory_map();
+
strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);

*cmdline_p = command_line;
--
2.11.0